1. Field of the Invention
The invention concerns a system consisting of at least two panels, in particular floor panels, wherein the two panels have a first lateral edge and a second lateral edge facing the first lateral edge, wherein the first lateral edge and the second lateral edge are designed to connect the first lateral edge of a panel with the second lateral edge of another panel by a movement substantially perpendicular to the covering, wherein the first lateral edge has a locking member and a spring means, wherein the second lateral edge has a locking element that cooperates with the locking member, wherein the locking member is movably designed so that the locking member with respect to the first lateral edge can adopt an outer position and an inner position, wherein the spring means is coupled to the locking member in such a way that the spring means in the inner position exerts a restoring force on the locking member in the direction of the outer position, wherein the locking member and the locking element each have a locking face and wherein in the connected state the locking faces of the locking element and of the locking member in the outer position are in contact with each other.
2. Description of Related Art
Panels of this kind can be joined together to create a covering, in particular a floor covering. The first and second lateral edges of adjacent panels are therefore formed to correspond with one another. The connection in each case of the first and second lateral edges of adjacent panels takes place by a movement running substantially perpendicular to the covering, in the case of a floor covering substantially vertical.
The panels therefore differ quite fundamentally from those in which the first and second lateral edges are angled in to each other by means of a swinging movement or are pushed into each other by a movement substantially parallel to the covering. Such panels are known for example from WO 97/47834 A1.
The first and second lateral edges of the panels of the kind mentioned at the outset have locking members and locking elements, which in the connected state come into engagement with each other. The panels can then no longer be lifted upwards against each other. Locking thus occurs substantially perpendicular to the covering. At the same time or by other means a locking of the panels substantially parallel to the covering can also take place. As a rule the first and second lateral edges of the panels can accordingly be laid without the use of glue or other securing elements such as screws or nails.
Floor panels in the main refer to laminate floor panels. Laminate floor panels as a rule have at least one layer with a resin-soaked decorative paper and at least one backing layer with a likewise resin-soaked paper on both sides of a so-called carrier layer. In panels with lacquered surfaces the decoration is printed on the carrier layer or another layer.
The carrier layer forming the base body of the panels is in particular made from a wood material. Wood materials include by way of example medium-density fibreboard (MDF), high-density fibreboard (HDF), chipboard and Oriented Strand Boards (OSB). Solid wood, wood-plastic composites or compact panels with pressed, resin-soaked paper as the carrier material can also be used.
Panels of the stated type are for example known from EP 1 518 032 A1. Here the first and second lateral edges of the panels opposing one another are designed to correspond with each other. The second lateral edge can be connected from above, that is to say substantially vertically to the covering, with the first lateral edge. In the connected state the panels can no longer be lifted upwards, since during connection a latching process between a locking lip and a locking groove of the lateral edges takes place.
The locking lip and locking groove are coordinated with one another in such a way that the locking groove presses against the locking lip when connected. The locking lip has the necessary flexibility in order that accordingly it can be pushed from an outer position to an inner position with respect to the first lateral edge. The flexibility of the locking lip is provided by a flexible groove adjacent to the locking lip, which if necessary can be filled with a medium in order to adjust the flexibility.
If the locking lip is forced into the inner position, the locking groove can slide over the locking lip. Then the locking lip springs back into its outer position and thereby engages back with the locking groove of the adjacent lateral edge. Thus corresponding locking faces of the locking lip and the locking groove come into contact with one another, which in each case are slightly inclined with respect to the plane of the covering. The necessary elasticity of the locking member for the springing back is also if necessary substantially provided by the spring means.
The locking lip is formed as one piece with the carrier layer of the panel. When connecting two lateral edges the locking lip can however break. If the elastic medium is a kind of glue, the locking lip remains secured to the panel despite such a break. The locking of the lateral edges perpendicular to the floor covering is thus retained. However a connection with a broken locking lip can only absorb reduced vertical extraction forces and this is a function of the elastic medium. Under high loading therefore a mismatch in the height of the connected panels can occur. If the loading increases further, as a result of the mismatch in height the panels can disengage from one another or the locking lips may snap off for good.